Ecological management and utilization method for space-limited L-shaped narrow slope abandoned mine land

Abstract

The invention discloses an ecological management and utilization method for a space-limited L-shaped narrow slope abandoned mine land, which is characterized in that a special-shaped staggered step slope platform is arranged on a slope to maximize the space utilization rate of the slope in a limited horizontal space, and the visual slope height is weakened and the overall safety and stability are improved through filling and shaping of a downtime; a foundation is laid for subsequent ecological construction and comprehensive utilization; a perfect drainage system is built, the stability of hydrological conditions in the site is guaranteed, and a good environment foundation is provided for ecological restoration and various activities; through an ecological restoration means, appropriate plant varieties are selected for planting, the ecological landscape is restored, and an ecological system is gradually reconstructed; through the treatment means, the convenient condition that people and vehicles can reach is finally achieved, meanwhile, the high-standard ecological treatment and utilization target of comprehensive utilization of agriculture and forestry travelers is achieved, the L-shaped narrow slope abandoned mine land with the limited horizontal space is enabled to have new vitality and vitality, and multiple improvement of ecological, economic and social values is achieved.

Description

Technical Field

[0001] This invention relates to an ecological management method for L-shaped narrow slope abandoned mining sites, specifically a method for the ecological management and utilization of space-constrained L-shaped narrow slope abandoned mining sites, belonging to the field of abandoned mining site management technology. Background Technology

[0002] Ecological restoration of abandoned mines is an important part of ecological civilization construction. Especially in regions of my country with a long history of mineral resource development, a large number of abandoned mines have formed steep slopes due to long-term mining. These slopes not only occupy land resources but also pose safety hazards such as landslides and collapses, while also disrupting the regional ecological balance. Therefore, it is urgent to achieve ecological restoration and land reuse through scientific management.

[0003] However, some abandoned mines, constrained by topography, surrounding buildings, or transportation facilities, have formed unique L-shaped narrow slope structures. These slopes have a significantly high ratio (height-to-width ratio) of vertical height to horizontal projection, and the horizontal spatial limitations are insurmountable. The projection range cannot meet the basic requirements for the design, construction, and functional layout of conventional abandoned mine sites. Specifically, the height-to-width ratio of rock-type L-shaped narrow slopes is ≥1.2, and that of soil / weathered rock L-shaped narrow slopes is ≥1.0. In some abandoned mine sites of this type, the horizontal projection width is strictly limited because the slope top is adjacent to a building complex or the planning boundary line is close to the slope top. Their "narrow and steep" morphological characteristics are fundamentally different from those of conventional abandoned mine slopes, making traditional treatment solutions difficult to adapt. The main problems are as follows: I. Conventional abandoned mining site remediation often adopts the "equal width stepped slope" model, which requires reserving sufficient horizontal projection space for setting up platforms and slopes of uniform width. However, the horizontal space of L-shaped narrow slopes is extremely limited. Slopes laid according to traditional methods will result in insufficient slope stability due to insufficient horizontal projection, or cause new geological disasters due to excessive slope cutting, making it impossible to achieve a balance between safety and space utilization.

[0004] Second, traditional slope treatment platform designs are mostly regular rectangular structures with adjacent platforms arranged independently, without considering staggered use of space. Within the limited horizontal range of an L-shaped narrow slope, it is difficult to develop sufficient usable space. The width design of conventional platforms cannot meet the combined needs of "safe passage + ecological restoration + functional layout", resulting in extremely low land use efficiency after treatment. Furthermore, there is a lack of comprehensive utilization planning that matches the space optimization design, making it difficult to achieve the dual goals of "ecological restoration + efficient land use". Treatment often only achieves basic ecological restoration effects and cannot meet the requirements of high-standard treatment.

[0005] Third, conventional treatment of abandoned mining sites mainly involves simple leveling without taking into account the steep characteristics of narrow slopes. This not only fails to reduce the visual slope height and improve overall stability, but also easily leads to drainage system failure and restricted vegetation growth due to poor connection between the slope and the quarry floor, affecting the sustainability of the treatment effect.

[0006] In summary, traditional remediation methods are clearly unsuitable for L-shaped narrow-slope abandoned mining sites with excessive aspect ratios and limited horizontal space, in terms of space utilization, safety and stability, ecological restoration effects, and comprehensive utilization. There is an urgent need for a specialized technical method that can adapt to these special conditions and achieve high-standard ecological remediation and efficient utilization. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to address the shortcomings of the existing technology by providing an ecological management and utilization method for L-shaped narrow slope abandoned mine sites with limited space, so as to achieve space utilization, safety and stability, ecological restoration and comprehensive utilization of L-shaped narrow slope abandoned mine sites with limited horizontal space, and promote the sustainable development of ecology and economy.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: An ecological restoration and utilization method for a spatially confined L-shaped narrow-slope abandoned mining site includes the following steps: (1) Upper platform: Conduct a safety assessment of the L-shaped narrow slope abandoned mine site with limited horizontal space that needs to be treated. Based on the site safety assessment results and topography, reduce the load on the slope to eliminate safety hazards, weaken human traces, and set up irregular staggered slope platforms. (2) Lower slope: The bottom of the L-shaped narrow slope abandoned mine is filled with slope to make it more compact and shape, thereby weakening the visual slope height and improving the overall safety and stability. (3) Drainage system construction: Construct a drainage system, which shall include at least slope drainage and quarry bottom drainage; (4) Ecological restoration, management and maintenance and assessment: Ecological restoration and greening of the L-shaped narrow slope abandoned mining area. After the ecological restoration is completed, a post-management and maintenance plan of no less than 3 years shall be formulated, a comprehensive assessment shall be carried out every two years, and maintenance and management measures shall be adjusted according to the assessment results. (5) Comprehensive utilization: If the direction of comprehensive utilization has been clearly defined in the preliminary plan, it shall be implemented in accordance with the defined direction; if it has not been clearly defined, the direction of utilization shall be determined comprehensively based on the nature of the land, the national land space regulations, the regional development requirements, etc.

[0009] In the above technical solution, in step (1), the space-constrained L-shaped narrow slope abandoned mine refers to an abandoned mine structure whose vertical height to horizontal projection ratio is significantly larger, and whose horizontal spatial constraints are insurmountable or whose projection range cannot meet the basic requirements of conventional abandoned mine design, construction and functional layout, and whose slope is located above the ground plane; the vertical height to horizontal projection ratio refers to the height-to-width ratio.

[0010] In the above technical solution, in step (1), the space-constrained L-shaped narrow slope abandoned mining site preferably refers to a rock slope with a height-to-width ratio ≥ 1.2, or a soil / weathered rock slope with a height-to-width ratio ≥ 1.0.

[0011] In the above technical solution, in step (1), before the slope safety treatment, a safety assessment should be conducted on the L-shaped narrow slope abandoned mine site. Based on the original topography and terrain, the slope should be cut and the load reduced to eliminate safety hazards such as loose rocks and loose stones and weaken human traces. According to the safety assessment results, for areas with poor stability, reinforcement technologies such as anchor bolts and anchor cables should be used for reinforcement and safety protection. Irregular staggered slope platforms should be set up to allow for platform penetration. The slope safety treatment and platform setting should fully consider the requirements for subsequent comprehensive utilization and eliminate visual pollution.

[0012] In the above technical solution, in step (1), the irregular staggered slope platform refers to an irregular platform with alternating superposition of adjacent upper and lower platforms, unequal widths at both ends, and linear or curved transitions; the maximum width of the platform is L, the minimum width is a·L, and the distance between the horizontal superposition of adjacent upper and lower platforms is (1-a)L / 2, where a is the ratio coefficient between the narrow end and the wide end of the platform, and its value range is 0<a<1; a connecting passage is provided between adjacent upper and lower platforms at the intersection for personnel or vehicles to go up and down; this irregular staggered slope platform is an irregular staggered slope platform that can significantly reduce the horizontal projection space of the slope.

[0013] In principle, the minimum platform width a·L should be ≥ 3.0m and the distance between adjacent upper and lower level platforms with overlapping horizontal spaces should be (1-a)L / 2 ≥ 1.5m; when the horizontal space is extremely limited, the value can be appropriately reduced.

[0014] In the above technical solution, when the connecting passage between platforms is only for pedestrians to go up and down, its slope ratio should not be greater than 1:2; when the ramp between platforms is needed for vehicles to go up and down, the maximum longitudinal slope should not be greater than 12%.

[0015] In the above technical solution, in step (2), the process of piling up and shaping the bottom of the L-shaped narrow slope abandoned mine refers to raising the terrain and relatively lowering the slope height. After the bottom of the mine is filled and shaped, the vertical height of the piled-up slope is not less than 1 / 5 of the original height of the narrow slope. The overall slope of the reshaped surface of the bottom of the mine is ≤45°. A platform or ramp that smoothly connects with the slope platform is set on the reshaped surface to realize the road setting.

[0016] In the above technical solution, the material used for filling and shaping is construction waste soil to alleviate the dilemma of urban construction waste disposal; the construction waste soil is foundation pit soil, the organic matter content shall not exceed 5%, and it shall not contain plant residues, humus, peat soil, construction waste, etc. The soil shall not be mixed with non-soil materials such as stones (particle size > 20cm), plastic products, and metal waste, and shall not contain toxic or harmful substances.

[0017] In the above technical solution, in steps (1) and (2), the upper platform and the lower slope should be treated in a coordinated manner, taking into account the conditions for subsequent use, so as to provide favorable prerequisites for subsequent use.

[0018] In the above technical solution, in step (3), slope drainage specifically refers to the drainage of the slope and platform generated by slope cutting and load reduction, which adopts a combination of intercepting ditch, platform drainage ditch, drainage hole and rapid flow channel: the intercepting ditch should be set at the top of the slope and the turning point of the slope, and be made of concrete. Its cross-section is trapezoidal or rectangular, and the specific size is determined according to the hydraulic calculation results; the platform drainage ditch is set at the foot of the slope of each level of platform, and is formed by manual excavation. Its cross-section is trapezoidal or rectangular, and the specific size is determined according to the hydraulic calculation results; drainage holes are set on the slope. The drainage holes are made of PVC pipes with a diameter of 5cm-10cm, with a horizontal spacing and a vertical spacing of 2m-3m, and an inclination angle of 10°-15°. The pipes are filled with gravel and other filter materials; when the slope length exceeds 50m and the slope is greater than 30°, a rapid flow channel should be set on the slope. The channel body is made of reinforced concrete structure with a wall thickness of not less than 20cm. Anti-slip sills are set in the channel. The height of the anti-slip sills is 10-15cm and the spacing is 1-1.5m.

[0019] In the above technical solution, in step (3), the drainage of the quarry bottom adopts open ditch drainage or pipeline drainage. When pipeline drainage is adopted, the main drainage pipe and branch drainage pipe are arranged. The main drainage pipe and branch drainage pipe are buried in the lower part of the quarry bottom slope. The main drainage pipe and branch drainage pipe adopt reinforced concrete pipe or corrugated pipe. The diameter of the main pipe is 60-100cm and the slope is not less than 0.3%. The diameter of the branch pipe is 30-50cm and the slope is not less than 0.5%. The specific dimensions are determined according to the hydraulic calculation results. When open ditch drainage is adopted, an open drainage ditch is dug. The cross-section of the open drainage ditch adopts trapezoidal cross-section or rectangular cross-section. The bottom width and top width are not less than 500mm. The depth is determined according to the hydraulic calculation. The slope of the open ditch is not less than 0.5%. The specific dimensions are determined according to the hydraulic calculation results.

[0020] In the above technical solutions, the drainage ditch and intercepting ditch of the platform adopt masonry, cast-in-place concrete or precast structure; the open drainage ditch at the bottom of the quarry adopts excavation, masonry, cast-in-place concrete or precast structure.

[0021] In the above technical solutions, the construction of the drainage system fully considers the needs of ecological maintenance.

[0022] In the above technical solution, the ecological restoration in step (4) refers to ecological revegetation, including but not limited to slope revegetation, slope platform revegetation, and quarry bottom revegetation. One or more vegetation restoration methods are selected according to local conditions, and native plants and recyclable environmentally friendly materials are given priority for revegetation. Trees, shrubs, and grasses are used where appropriate, and trees, shrubs, and grasses are combined.

[0023] In the above technical solution, the slope revegetation mainly adopts topsoil spraying, the slope platform revegetation is covered with planting soil with a thickness of not less than 0.8m, the slope platform revegetation is carried out by planting hanging plants on the outer edge of the platform and climbing plants on the inner edge of the slope foot to maximize the coverage of the bare slope surface, and trees and shrubs are planted as needed; the bottom of the quarry is covered with planting soil with a thickness of not less than 0.8m before revegetation, and the revegetation is carried out by combining grass seeding and planting of trees and shrubs.

[0024] In the above technical solution, the post-maintenance management mentioned in step (4) refers to the formulation of a post-maintenance management plan for a period of not less than 3 years after the completion of ecological governance and utilization. This includes regular watering, fertilization, pruning, and pest and disease control for vegetation; conducting a comprehensive vegetation inspection once each spring and autumn and replanting dead or poorly growing plants in a timely manner; regularly dredging and clearing the drainage system and conducting a comprehensive inspection at least once a year to ensure smooth drainage; and conducting long-term tracking and evaluation of the ecological environment changes after the ecological governance and utilization of the L-shaped narrow slope abandoned mine site, conducting a comprehensive evaluation every two years, and adjusting maintenance management measures according to the evaluation results to ensure the long-term effectiveness and sustainability of ecological governance and utilization.

[0025] In the above technical solution, the comprehensive utilization in step (5) can refer to the following directions: A. Land designated as agricultural land or agricultural space in the national land use plan: If the mining site is located in an agricultural space area in the national land use plan, the restoration direction should prioritize restoring agricultural production functions, such as cultivating where suitable, creating gardens where suitable, afforesting where suitable, and watering where suitable; if agricultural production functions cannot be restored, ecosystem functions should be restored.

[0026] B. Land designated as agricultural land or ecological space in the national land use plan: Mining sites located within ecological zones of the national land use plan should prioritize the restoration of the ecosystem, prohibiting any development of the living ecosystem's functions. Within the ecological protection red line, any alteration or change of the land's use is prohibited. Outside the ecological protection red line, moderate land development, resource and landscape utilization may be considered, provided it does not impair existing ecological functions, but irreversible changes such as construction and occupation are strictly limited.

[0027] C. Land designated for construction or urban space in the national land use plan: If the mining site is located in an urban space area in the national land use plan, the restoration direction should prioritize restoring the conditions for urban development and utilization, and revitalizing the use of industrial and mining wasteland. If the mining site and its surrounding natural ecological landscape are good, or if the mining site has a long history of mining development, precious mining relics and rich mining culture, the creation of a mining theme park can be considered to improve the ecological quality of the city. If the conditions for urban development and utilization cannot be restored, the ecosystem function should be restored and the ecological quality improved.

[0028] Compared with existing technologies, it has the following characteristics: (1) Given the inherent limitation of horizontal space in L-shaped narrow-slope abandoned mining areas, a staggered, irregularly shaped slope platform was constructed. Compared to the traditional "equal-width stepped slope" method, this significantly reduced the horizontal space required for slope excavation and created sufficient usable space within the limited horizontal projection area. Specifically: Assuming the traditional "equal width stepped slope" mode is set n Steps, each step is [width] l The height of each step is h The aspect ratio is 1: α (The aspect ratio refers to the ratio of the vertical projection height to the horizontal projection width of the slope surface. 'l' represents the width of the platform and should not be confused with the horizontal projection distance of the slope. The aspect ratio is taken as 1.) α For ease of calculation, the horizontal projection width is expressed as follows when the vertical projection height is 1. α The required horizontal sloping distance from the bottom to the top of the slope is:

[0029] Assuming the irregular staggered slope platform mode is set n Steps, each step has a maximum width of l minimum width α·l The height of each step is h The aspect ratio is 1: α The required horizontal sloping distance from the bottom to the top of the slope is:

[0030] when n =12, l=12 m , α =0.25, h =8 m Aspect Ratio 1: α When the ratio is 1:0.6, L 1 =189.6 m , L 2 =152.1 m Compared to the traditional "equal width stepped slope" mode, the irregular staggered slope platform mode can shorten the horizontal slope distance by 37.5m and 19.87% under the same number of steps, step height, and slope height-to-width ratio.

[0031] (2) Compared with traditional simple slope cutting, after restoration, the slope is inaccessible to people and vehicles, and the slope cannot be utilized. The vegetation maintenance of the slope is also very difficult, and ecological restoration can only be achieved slowly by relying on natural conditions. The method proposed in this invention achieves the purpose of restoration and utilization that is accessible to people and vehicles through scientific and reasonable slope cutting and load reduction, graded slope release, and setting up steps and ramps that meet the requirements. It not only facilitates the restoration construction, but also provides greater possibilities for later maintenance and utilization. After restoration, the abandoned mining area is truly revitalized.

[0032] (3) Collaborative management of slope and quarry bottom: by raising the elevation of the quarry bottom, the slope height is relatively reduced, the visual impact is weakened, and the entire site is connected by the slope ramps and quarry bottom roads, so that the entire site is visible and accessible to vehicles and people.

[0033] (4) Combining the treatment of abandoned mining sites with the disposal of construction waste turns construction waste into treasure, which not only improves the ecology of abandoned mining sites, but also solves the embarrassing situation of construction waste having nowhere to go. At the same time, it reduces the treatment cost of abandoned mining sites and achieves the beneficial effect of 1+1>2.

[0034] (5) Reasonable topographic reshaping and drainage system construction can achieve landscape harmony and ecological naturalness, creating favorable conditions for the subsequent use of abandoned mining sites. It can realize multi-functional use, such as the construction of parks and ecological agricultural areas, which has significant economic and social benefits.

[0035] (6) Long-term tracking, evaluation and maintenance management plans ensure the long-term stability and sustainability of the ecological governance and utilization effects. Attached Figure Description

[0036] Figure 1 This is a flowchart of the ecological restoration method for L-shaped narrow slope abandoned mining sites according to the present invention; Figure 2 This is an engineering plan view of the L-shaped narrow slope abandoned mining site in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of a typical form of the irregular staggered slope platform in the L-shaped narrow slope abandoned mine site in Embodiment 1 of the present invention; Figure 4 : This is a plan view of the drainage system of the L-shaped narrow slope abandoned mine site in Embodiment 1 of the present invention; Figure 5 : This is a cross-sectional view of the slope drainage system and platform revegetation of the L-shaped narrow slope abandoned mine site in Embodiment 1 of the present invention.

[0037] Among them: 0-Remediation red line; 1-Irregular staggered platform; 2-Connecting passage; 3-Slope at the bottom of the quarry; 4-Road at the bottom of the quarry; 5-Retaining dam; 6-Intercepting ditch; 7-Platform drainage ditch; 8-Rapid flow channel; 9-Energy dissipation pool; 10-Ecological pond; 11-Platform soil cover; 12-Retaining wall; 13-Thick layer of substrate sprayed with netting; 14-Climbing plants; 15-Hanging plants; 16-Shrubs; 17-Drainage hole; 18-Open drainage ditch. Detailed Implementation

[0038] The following describes in detail the specific embodiments of the technical solution of the present invention, but the present invention is not limited to the following description: This invention provides a method for the ecological management and utilization of a space-constrained L-shaped narrow slope abandoned mining site, the flowchart of which is shown below. Figure 1 As shown, it includes the following steps: (1) Upper platform: Conduct a safety assessment of the L-shaped narrow slope abandoned mine site with limited horizontal space that needs to be treated. Based on the site safety assessment results and topography, reduce the load on the slope to eliminate safety hazards, weaken human traces, and set up irregular staggered slope platforms. (2) Lower slope: The bottom of the L-shaped narrow slope abandoned mine is filled with slope to make it more compact and shape, thereby weakening the visual slope height and improving the overall safety and stability. (3) Drainage system construction: Construct a drainage system, which shall include at least slope drainage and quarry bottom drainage; (4) Ecological restoration, management and maintenance and assessment: Ecological restoration of the L-shaped narrow slope abandoned mining site shall be carried out. After the ecological restoration is completed, a post-maintenance and management plan of no less than 3 years shall be formulated, a comprehensive assessment shall be carried out every two years, and maintenance and management measures shall be adjusted according to the assessment results. (5) Comprehensive utilization: If the direction of comprehensive utilization has been clearly defined in the preliminary plan, it shall be implemented in accordance with the defined direction; if it has not been clearly defined, the direction of utilization shall be determined comprehensively based on the nature of the land, the national land space regulations, the regional development requirements, etc.

[0039] The present invention will now be described in conjunction with specific embodiments: Example 1

[0040] In this embodiment, the remediation of a certain abandoned mining site is carried out. This abandoned mining site is an L-shaped narrow-slope abandoned mining site with limited horizontal space, and its plan is shown below. Figure 2 As shown, the original maximum slope height was approximately 88m, with a slope angle of 60° and a height-to-width ratio of 1.73. The treatment boundary line 0 is close to the original slope crest line, limiting the horizontal slope space. It is a typical L-shaped narrow slope abandoned mining site (rock slope) with limited horizontal space. The original vegetation has been completely destroyed, the slope morphology is chaotic, the bedrock is exposed, the rocks are relatively broken, and there are loose rocks, resulting in serious visual pollution. The quarry bottom after the stone mining was completed is filled with mud, stones, garbage, etc., and the environmental condition is poor. It is urgent to carry out visual pollution control, ecological restoration, and ecological revegetation, and to carry out high-standard comprehensive utilization under the premise of permissible conditions.

[0041] Governance strategy: Through careful design, we aim to achieve high-standard restoration of abandoned mining sites, ensuring safety and stability, ecological restoration, and landscape harmony, while also realizing high-quality comprehensive utilization that allows for accessibility by people and vehicles and integrated use of agriculture, forestry, and tourism.

[0042] The specific implementation steps are as follows: (1) Upper step back: Before slope safety treatment, a safety assessment was conducted on the L-shaped narrow slope abandoned mining site. Based on the original topography and terrain, slope reduction and load reduction were implemented, loose rocks and dangerous stones were removed, safety hazards were eliminated, and human traces were minimized. For areas with poor stability, reinforcement techniques such as anchor bolts and cables were used for reinforcement and safety protection based on the safety assessment results. An 8-level irregular staggered platform 1 was installed. A typical schematic diagram of the irregular staggered platform 1 is shown below. Figure 3 As shown: The elevations of the irregular staggered platform 1 from bottom to top are +24m, +32m, +40m, +56m, +64m, +72m, and +80m. The maximum width of the platform is 6.0m, and the minimum width is 3.0m. The height difference between adjacent irregular staggered platforms 1 is 8.0m, and the height-to-width ratio is 1:2. The irregular staggered platforms 1 at each level are connected by connecting passages 2. In this embodiment, the connecting passage 2 is a pedestrian staircase, 1.5m wide, with a slope ratio of 1:2. When other projects require vehicular access and conditions permit, the connecting passage 2 can be set as a car ramp, with a maximum slope not exceeding 12%. After slope clearing, unstable sections are reinforced with random anchor bolts combined with active protective netting to ensure the stability of the rock mass. Finally, safety guardrails are installed at the outer edge of the slope crest to prevent people and animals from accidentally entering.

[0043] (2). Lower slope: To mitigate the visual slope height of an abandoned L-shaped quarry, the bottom of the quarry is filled and reshaped to improve overall safety and stability. Figure 2As shown, the filling height of the quarry bottom slope 3 is 24m, exceeding 1 / 5 of the total height of the narrow slope. In this embodiment, the quarry bottom space is ample, resulting in a gentle slope; the overall slope of the reconstructed quarry bottom surface is approximately 7°. Quarry bottom slope 3 reduces the visual height of the original narrow slope from 88m to 64m, significantly eliminating the visual oppressive feeling of the steep narrow slope. Furthermore, as a counterweight layer, quarry bottom slope 3 greatly enhances the overall safety of the project.

[0044] Construction waste was used as the filling material. To ensure project safety, a retaining dam 5 was installed at the bottom of the fill slope. Quarry bottom ramps 4, each 8.0m wide, were constructed on both sides of the quarry bottom slope 3. The starting point of the quarry bottom ramps 4 connects to the off-site road, and the ending point connects to the irregular staggered platform 1, enabling vehicles to ascend the slope. During the construction phase, the quarry bottom ramps 4 also served as a construction road and functioned as an earth-rock dam. Whether or not a structural layer will be added after the treatment is completed will be determined based on usage requirements.

[0045] (3) Drainage system construction: like Figure 4 and Figure 5 As shown, based on the topography, intercepting ditches 6 are set up at the outer edge of the slope crest at the end of the treatment area; platform drainage ditches 7 are set up at the foot of the various irregular staggered platforms 1; rapid flow channels 8 are set up between the platforms; energy dissipation pools 9 are set up at the bottom of the rapid flow channels; drainage ditches 18 are set up on the outside of the quarry bottom slope 4; and an ecological pond 10 is set up at the bottom of the quarry. The effective connection between the platform drainage ditches 7 and the intercepting ditches 6 is ensured, and the regional water catchment flows through the intercepting ditches 6, drainage ditches 7, and rapid flow channels 8 to the ecological pond 10. The ecological pond 10 serves both landscaping and vegetation maintenance functions.

[0046] The intercepting ditch 6 and the drainage ditch 18 are made of concrete with a rectangular cross section, a concrete wall thickness of 20cm, and a water passage cross section size of 600mm×600mm.

[0047] The platform drainage ditch 7 is formed by on-site excavation. Its cross-sectional shape is an inverted trapezoid, with a top width of 30cm, a bottom width of 20cm, and a depth of 30cm.

[0048] The drainage hole 17 is made of PVC pipe with a diameter of 10cm, with a horizontal and vertical spacing of 2m and an inclination angle of 15°, and the pipe is filled with filter gravel.

[0049] The rapid flow channel 8 is constructed of reinforced concrete with a wall thickness of 20cm. Anti-slip barriers are installed inside the channel, with a height of 15cm and a spacing of 1m.

[0050] (4) Ecological restoration, management, maintenance and assessment: Ecological restoration is a site-wide process, with the following methods for each unit: slope surfaces are treated with thick-layered substrate hydroseeding with wire mesh; slope platforms are treated with soil covering + grass seeding + shrub planting; the reconstructed quarry floor surface is treated with grass seeding; the quarry floor platform is treated with 1.0m of soil covering + grass seeding; temporary pavements are treated with grass seeding; and roadbed slopes, small retaining dam slopes, and slopes less than 4m in height are treated with topsoil hydroseeding. Among these, slope platform revegetation includes... Figure 5 As shown, a concrete retaining wall 12 with a height of 0.5m is set along the outer edge of the irregular staggered platform 1. The inner side of the retaining wall is covered with soil to form the platform cover soil 11. A drainage ditch 7 is set at the foot of the slope. The thickness of the platform cover soil 11 is 0.5m~1.5m. Grass seeds are sown on the surface of the platform cover soil and shrubs 16 are planted. The slope surface is sprayed with a thick layer of netting substrate to form a thick layer of netting substrate spraying layer 13. Hanging plants 15, such as yellow jasmine, are planted along the outer edge of the irregular staggered platform 1, and climbing plants 14, such as Virginia creeper, are planted along the inner side of the irregular staggered platform 1, in order to completely cover the bare slope surface and eliminate visual pollution.

[0051] Post-maintenance management includes irrigation, pest and disease control, substrate repair, re-spraying, thinning, and covering with shade netting. The goal of maintenance is to achieve the design requirements and ultimately establish a near-natural vegetation that blends with the surrounding environment. A comprehensive assessment is conducted every two years, and maintenance management measures are adjusted based on the assessment results.

[0052] (5) Comprehensive utilization: The site is close to a reservoir and boasts abundant scenic resources. Its comprehensive utilization direction is to create a popular spot for social media check-ins that integrates leisure and entertainment.

[0053] Through the above methods of treatment, the site achieved the following benefits: 1. Economic benefits: Low maintenance costs; transforming the site into a popular tourist destination will boost regional economic development. 2. Landscape benefits: The slope is modified according to the original topography, resulting in a natural slope and beautiful landscape; 3. Safety benefits: By reshaping the quarry bottom terrain, the slope elevation difference is reduced, improving overall safety; 4. Comprehensive benefits: The pit bottom and the slope are interconnected and accessible to people and vehicles, making full use of the resources.

[0054] The above examples are merely illustrative of the technical concept and features of the present invention and should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the essence of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for the ecological restoration and utilization of a spatially confined L-shaped narrow-slope abandoned mining site, characterized in that, Includes the following steps: (1) Upper platform: Conduct a safety assessment of the L-shaped narrow slope abandoned mine site with limited horizontal space that needs to be treated. Based on the site safety assessment results and topography, reduce the load on the slope to eliminate safety hazards, weaken human traces, and set up irregular staggered slope platforms. (2) Lower slope: The bottom of the L-shaped narrow slope abandoned mine is filled with slope to make it more compact and shape, thereby weakening the visual slope height and improving the overall safety and stability. (3) Drainage system construction: Construct a drainage system, which shall include at least slope drainage and quarry bottom drainage; (4) Ecological restoration, management and maintenance and assessment: Ecological restoration and greening of the L-shaped narrow slope abandoned mining area. After the ecological restoration is completed, a post-management and maintenance plan of no less than 3 years shall be formulated, a comprehensive assessment shall be carried out every two years, and maintenance and management measures shall be adjusted according to the assessment results. (5) Comprehensive utilization: If the direction of comprehensive utilization has been clearly defined in the preliminary plan, it shall be implemented in accordance with the defined direction; if it has not been clearly defined, the direction of utilization shall be determined comprehensively based on the nature of the land, the national land space regulations, the regional development requirements, etc.

2. The ecological governance method according to claim 1, characterized in that, In step (1), the space-constrained L-shaped narrow slope abandoned mine refers to an abandoned mine structure whose vertical height to horizontal projection ratio is significantly larger, and whose horizontal spatial constraints are insurmountable or whose projection range cannot meet the basic requirements of conventional abandoned mine design, construction and functional layout, and whose slope is located above the ground plane; the vertical height to horizontal projection ratio refers to the height-to-width ratio.

3. The ecological governance method according to claim 2, characterized in that, In step (1), the space-constrained L-shaped narrow slope abandoned mining site refers to a rock slope with a height-to-width ratio ≥ 1.2, or a soil / weathered rock slope with a height-to-width ratio ≥ 1.

0.

4. The ecological governance method according to claim 1, characterized in that, In step (1), the irregular staggered ramp platform refers to an irregular platform with alternating and overlapping spaces between adjacent upper and lower platforms, unequal widths at both ends, and linear or curved transitions; the maximum width of the platform is L, the minimum width is a·L, and the distance between the horizontal spaces of adjacent upper and lower platforms is (1-a)L / 2, where a is the ratio coefficient between the narrow end and the wide end of the platform, and its value range is 0 < a < 1; a connecting passage is provided between adjacent upper and lower platforms at the intersection for personnel or vehicles to go up and down.

5. The ecological governance method according to claim 4, characterized in that, The minimum width of the irregular staggered ramp platform should be ≥3.0m, and the horizontal spacing between adjacent upper and lower level platforms should be ≥1.5m. When the connecting passage between platforms is only for pedestrians to go up and down, its slope ratio should not be greater than 1:

2. When there is a need for vehicles to go up and down the ramp between platforms, the maximum longitudinal slope should not be greater than 12%.

6. The ecological governance method according to claim 1, characterized in that, In step (2), the process of piling up and shaping the bottom of the L-shaped narrow slope abandoned mine refers to raising the terrain and relatively lowering the slope height. After the bottom of the mine is filled and shaped, the vertical height of the piled-up slope is not less than 1 / 5 of the original height of the narrow slope. The overall slope of the reshaped surface of the bottom of the mine is ≤45°. A platform or ramp that smoothly connects with the slope platform is set on the reshaped surface to realize the road setting.

7. The ecological governance method according to claim 1, characterized in that, In step (3), surface drainage specifically refers to the drainage of the slope and platform generated by slope cutting and load reduction. It adopts a combination of intercepting ditches, platform drainage ditches, drainage holes and rapid flow channels: the intercepting ditch should be set at the top of the slope and at the turning point of the slope, and should be made of concrete. Its cross-section is trapezoidal or rectangular, and the specific size is determined according to the hydraulic calculation results; the platform drainage ditch is set at the foot of the slope of each level of platform, and is formed by manual excavation. Its cross-section is trapezoidal or rectangular, and the specific size is determined according to the hydraulic calculation results; drainage holes are set on the slope. The drainage holes are made of PVC pipes with a diameter of 5cm-10cm, with a horizontal spacing and a vertical spacing of 2m-3m and an inclination angle of 10°-15°. The pipes are filled with gravel and other filter materials; when the slope length exceeds 50m and the slope is greater than 30°, a rapid flow channel should be set on the slope. The channel body is made of reinforced concrete structure with a wall thickness of not less than 20cm. Anti-slip barriers are set in the channel. The height of the anti-slip barriers is 10-15cm and the spacing is 1-1.5m.

8. The ecological governance method according to claim 1, characterized in that, In step (3), the drainage of the quarry bottom is carried out by open ditch drainage or pipeline drainage. When pipeline drainage is used, the main drainage pipe and branch drainage pipe are arranged. The main drainage pipe and branch drainage pipe are buried in the lower part of the quarry bottom slope. The main drainage pipe and branch drainage pipe are made of reinforced concrete pipe or corrugated pipe. The diameter of the main pipe is 60-100cm and the slope is not less than 0.3%. The diameter of the branch pipe is 30-50cm and the slope is not less than 0.5%. When open ditch drainage is used, an open drainage ditch is dug. The cross-section of the open drainage ditch is trapezoidal or rectangular. The bottom width and top width are not less than 500mm and the slope of the open ditch is not less than 0.5%.

9. The ecological governance method according to claim 1, characterized in that, In step (4), the ecological restoration refers to ecological revegetation, including but not limited to slope revegetation, slope platform revegetation, and quarry bottom revegetation, and one or more vegetation restoration methods are selected according to local conditions.

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